SOLUTION: Write the standard equation of the parabola given the two endpoints of the focal width ; (-2,3) and (5,3) with p>0

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Question 1167661: Write the standard equation of the parabola given the two endpoints of
the focal width ; (-2,3) and (5,3) with p>0

Answer by Edwin McCravy(20059) About Me  (Show Source):
You can put this solution on YOUR website!
Instead of doing your problem for you, I'll do one exactly like yours step-by-
step.  This is the problem I will do for you.  Use it as a model to do yours by:
Write the standard equation of the parabola given the two endpoints of
the focal width ; (-4,5) and (9,5) with p>0

The equation has the standard form:

%28x-h%29%5E2=4p%28y-k%29  with p positive

where
the focus is the midpoint between the endpoints of the 
focal chord (also called the latus rectum)
4p = the focal width = distance between the two endpoints
p = the distance from the focus to the vertex 
(h,k) = the vertex, which has the same x-coordinate as the focus.

the focus is the midpoint between (-4,5) and (9,5) which is 


I'll plot the end points of the focal width, and the focus:



4p = the focal width = distance between the two endpoints, 


4p=13
p=13%2F4

p = the distance from the focus to the vertex.

So we subtract 13/4 from the y-coordinate of the focus:
The y-coordinate of the focus is 5, so
5-13%2F4=20%2F4-13%2F4=7%2F4

So the vertex is

%28matrix%281%2C3%2C5%2F2%2C%22%2C%22%2C7%2F4%29%29

I'll plot the vertex:



and sketch in the parabola:



So the standard equation of the parabola is

%28x-h%29%5E2=4p%28y-k%29

%28x-5%2F2%29%5E2=13%28y-7%2F4%29

Now do yours exactly step-by-step the same way.

Edwin